refactor(mcp): remove websearch_exa as built-in MCP server

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src/mcp/index.ts

@@ -1,4 +1,3 @@
-import { websearch_exa } from "./websearch-exa"
 import { context7 } from "./context7"
 import { grep_app } from "./grep-app"
 import type { McpName } from "./types"
@@ -6,7 +5,6 @@ import type { McpName } from "./types"
 export { McpNameSchema, type McpName } from "./types"
 
 const allBuiltinMcps: Record<McpName, { type: "remote"; url: string; enabled: boolean }> = {
-  websearch_exa,
   context7,
   grep_app,
 }